Arduino has taken the product “maker” world by storm and one of the more popular Arduino modules is the Analog Devices AD9851 DDS waveform generator. Internet forums are filled with discussions related to two specific issues. One issue is that the output amplitude is not constant with frequency, requiring a level control loop. The second issue is that the distortion gets pretty horrific, particularly at higher output frequency settings. In this article, we’ll show how to correct these issues, as well as providing some additional tips for improving the quality of the output.